Achatinella is a very peculiar group of land shells, found only in the Pacific Islands. They are all small, and so remarkably beautiful, that the natives use them for ornaments. It was under this form that seven different species came into our possession on the return of Captain, now Lord Byron, from his voyage to the South Seas. As the systematic conchologist will find them fully described in the Journal above quoted, we now only illustrate them by figures. ---- ACHATINELLA perversa, _fig. 2._ ---- SPECIFIC CHARACTER. _Shell reversed, sub-trochiform, fulvous brown with darker transverse bands and longitudinal lines; apex and suture white._ Achatinella perversa. _Swains. Monog. No. 2, p. 84._ Our figures of this elegant species are somewhat larger than nature. ---- ACHATINELLA Acuta, Fig. 3. ---- SPECIFIC CHARACTER. _Shell ovate-oblong, chesnut, with a marginal fulvous band; spire somewhat lengthened, acute, the tip black._ Achatinella acuta _Sw. Monog. No. 3, p. 84._ Shell somewhat pyriform, the spire being pointed, and considerably longer than the aperture: In these respects it differs considerably from the two preceding, but the great peculiarity of the twisted and truncated columella or pillar, sufficiently points it out as belonging to this group. * * * * * * [Illustration: MURICINÆ. Pl. 3. _Murex eurystomus_] MUREX (_Centronotus_) eurystomus, _Wide mouthed Murex_. ---- Family Cassidæ, Sub-family Muricinæ, _Nob._ Genus. Murex _Auct._ SYNOPSIS OF THE SUB-GENERA. 1. _Typical._ Canal very long: Shell armed with tooth-like spines mostly arranged in three varices MUREX _Auct._ 2. _Sub-Typical_ (?). Canal very long: Shell without spines, varices tuberculated. HAUSTELLARIA. _Sw._ 3. _Aberrant._ Canal moderate: Shell with foliated or compressed varices. 1. Varices foliated, mostly three. PHYLLONOTUS. _Sw._ 2. Varices numerous, mostly acute. CENTRONOTUS. _Sw._ 3. Varices compressed, fin shaped. PTERYNOTUS. _Sw._ ---- SPECIFIC CHARACTER. _Shell with from 7 to 8 simple foliated varices; body whorl with three brown bands; aperture effuse, tinged with rosey; umbelicus very large._ Murex Saxatilis. _Auct. Lamark. 7. p. 167. Martini. pl. 108. f. 1013._ ---- We feel some surprize that Lamark should have viewed this large and imposing _Murex_ as one of the varieties of _Saxatilis,_ from which it is unquestionably distinct. It is by no means common, nor do we know its precise locality.